穗肥施用时期对水稻氮素利用及产量的影响

以越光和武香粳 9号为材料研究了不同穗肥施用时期施氮对水稻氮素利用及产量的影响。结果表明 :倒 1 5叶 ,倒 2 5和 0 5叶 ,倒 3 5、 2 5和 1 5叶施肥提高了花后高效叶片叶绿素含量和含氮率。穗肥施用提高了水稻的产量 ,倒3 5、 2 5和 1 5叶 ,倒 3 5和 1 5叶 ,倒 2 5叶施肥对增加两品种产量 ,提高穗肥利用率和生产力作用显著。施用穗肥增产的机制两品种表现不一致 :越光主要表现在结实率的提高 ,武香粳 9号主要表现为每穗总粒数的增加。生育期较短的越光穗肥利用率略低于生育期较长的武香粳 9号。

Effect of application stage of panicle fertilizer on rice grain yield and the utilization of nitrogen

Effect of application stage of panicle fertilizer on the rice grain yield and quality was studied with two Japonica rice(Koshihikari and Wuxiangjing 9).The results were showed as follows:panicle fertilizer was applied at 1.5 leaves from top(LFT),2.5 and 0.5 LFT,and 3.5,2.5 and 1.5 LFT could increase the chlorophyll and nitrogen content of higher effective leaves,and thus increased the rice yield.The yield increment for Koshihikari mainly resulted from the percentage of ripen grain,as a contrast,Wuxiangjing 9 resulted from the increment of the grain number per panicle.Panicle fertilizer was applied at 3.5,2.5 and 1.5 LFT,3.5 and 1.5 LFT, and 2.5 LFT could increase the rate of panicle fertilizer utilization, the productivity of panicle fertilizer in two varieties.Nitrogen use efficiency of panicle fertilizer of Koshihikari was lower than that of Wuxingjing 9.